I have such a cloak. My price is... two Duels Arcane. I know of your power, and wish to test myself.

The first duel will be with all of our usual trappings. 3 defensive or enhancing spells cast beforehand, no healing potions, scrolls, or kits. No melee. Achieve victory through Arcane power alone.

The second duel shall be with no magical items whatsoever. 3 defensive or enhancing spells cast beforehand. No epic spells.

If I am defeated, for the humbling lesson, I shall grant you the cloak free of conditions. If it is I who instructs you, then the cloak shall be yours with one condition: On pain of eternal petrification, you shall enter into a binding blood contract to never willingly kill, or ingest the blood of, a goodly Dragon for the rest of your existence. What say you?

All of this being contingent on my being the victor, of course, but my intent is that you not kill any goodly dragons willingly, whether in self-defense or by accident when fighting nearby them.

Self-defense is a willing act that can be used in lieu of escaping the conflict, which I am sure you are more than capable of. I would not be satisfied to leave open the loophole of a good dragon loosing its life because you chose to stand your ground after angering it.

I do not believe I can accept your modification and keep my intent intact. You may always choose to bypass or escape conflict to avoid needing to kill such a magnificent beast. Self-defense would also allow for "accidentally" slaying one of their kind which is also something that would be contrary to the intended goal.

Perhaps, if my stated condition is not to your liking, we can simply call the whole thing off.